The present invention relates to a method of producing ventilated cigarettes.
So-called "ventilated" cigarettes are produced using perforating devices normally forming part of a filter assembly machine, and the perforating "tool"of which consists of a focused laser beam.
On filter assembly machines of the type described, for example, in British patent n. 2,241,866, filter-tipped cigarettes are produced from a succession of first tobacco items consisting of double cigarette portions which, traveling transversely through a first cutting station along a path defined by the filter assembly machine, are each cut into two single portions to form a first and second orderly succession arranged side by side and parallel to each other. At a rolling station along the aforementioned path, each cigarette portion in one of the two successions is connected to a corresponding portion in the other succession to form a second tobacco item hereinafter referred to as a "double cigarette", and each of which consists of two cigarette portions separated by a double filter connected integral with the two cigarette portions by a connecting band, the central portion of which encloses the double filter, and the end portions of which each enclose one end of a respective cigarette portion.
According to the above British patent, once formed, the double cigarettes are fed successively through a second cutting station where they are cut transversely in half to form two successions of third tobacco items consisting of oppositely oriented single cigarettes. That is, downstream from the cutting station, the single cigarettes in each pair formed by cutting a respective double cigarette are arranged with their filters facing and substantially contacting each other.
Patent DE-41 08 166 relates to a filter assembly machine presenting a perforating station where the double cigarettes are rolled about their axis and simultaneously perforated with ventilation holes by a laser device designed to emit pairs of pulsating focused laser beams.
Such a method presents serious drawbacks due to the rolling operation which, if harmful to single cigarettes, is even more so when applied to double cigarettes which, on account of their length, are subject not only to tobacco fallout but also to breakage.